The definition of only is alone or by itself.(adjective)
An example of only used as an adjective is in the phrase "the only house left standing," which means the house is by itself.
Only is defined as no other or nothing more.(adverb)
An example of only used as an adverb is in the phrase "only walking," which means doing nothing other than walking.
Only means but or except that.(conjunction)
An example of only used as a conjunction is in the sentence "I would have eaten that hamburger, only it was undercooked," which means "I would have eaten that hamburger, but it was undercooked."
See only in Webster's New World College Dictionary
Origin: ME < OE anlic < an, one + -lic, -ly
See only in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English ānlīc
Origin: : ān, one; see one
Origin: + -līc, having the form of; see -ly1. Usage Note: When used as an adverb, only should be placed with care to avoid ambiguity. Generally this means having only adjoin the word or words that it limits. Variation in the placement of only can change the meaning of the sentence, as the following examples show: Dictators respect only force; they are not moved by words. Dictators only respect force; they do not worship it. She picked up the receiver only when he entered, not before. She only picked up the receiver when he entered; she didn't dial the number. Though strict grammarians insist that the rule for placement of only should always be followed, there are occasions when placement of only earlier in the sentence seems much more natural, and if the context is sufficiently clear, there is no chance of being misunderstood. In the following example only is placed according to the rule: The committee can make its decision by Friday of next week only if it receives a copy of the latest report. Placement of only earlier in the sentence, immediately after can, would warn the reader that a condition on the statement follows. See Usage Note at not.
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